From 7c901071a1168d41905025177f1a7d5f6b873f7f Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 21:18:15 +0200
Subject: [PATCH 1/8] Refactor

---
 drivers/vga.c   | 20 +++++++++++++-------
 kernel/kernel.c |  2 ++
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/vga.c b/drivers/vga.c
index 3ea9cf6..c2e1dbe 100644
--- a/drivers/vga.c
+++ b/drivers/vga.c
@@ -5,8 +5,11 @@
 // Charpos = 0xb8000 + 2(row*80 + col)
 
 // Memory
-#define VIDEO_MEM 	(char*)0xb8000
-#define VIDEO_MEM_MAX	(char*)0xb8fa0
+#define VGA_ADDRESS 	(char*)0xb8000
+#define VGA_ADDRESS_MAX	(char*)0xb8fa0
+
+#define MAX_ROWS 25
+#define MAX_COLS 80
 
 // Global
 static unsigned int cursor_row = 0;
@@ -16,12 +19,15 @@ static unsigned int cursor_col = 0;
 	VGA & Memory Functions
 */
 char* get_vga_charpos_pointer(unsigned int col, unsigned int row) { 
-	return (char*)(VIDEO_MEM + 2*((row*80) + col)); 
+	return (char*)(VGA_ADDRESS + 2*((row*80) + col)); 
 }
 
 void writechar(char c, unsigned int col, unsigned int row, int attribute_byte) {
+	if( !attribute_byte ) 
+		attribute_byte = 0x0f;
+
 	char* mem = get_vga_charpos_pointer(col, row);
-	*mem = c; 		// Write the character
+	*mem = c; 			// Write the character
 	*(mem+1) = attribute_byte;	// Write the attribute_byte
 
 }
@@ -30,9 +36,9 @@ void writechar(char c, unsigned int col, unsigned int row, int attribute_byte) {
 	Graphics Functions
 */
 void clear_screen() {
-	// Make all the characters spaces
-	for( char* c = VIDEO_MEM; c <= VIDEO_MEM_MAX; c += 2 )
-		*c = 0x20;
+	for( int c = 0; c < MAX_COLS; c++ )
+		for( int r = 0; r < MAX_ROWS; r++ )
+			writechar(0x20, c, r, 0x0);
 }
 
 void disable_vga_cursor() {
diff --git a/kernel/kernel.c b/kernel/kernel.c
index 2d24fd9..2620165 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -1,3 +1,5 @@
+#define NULL ((void*)0x0)
+
 #include "../drivers/vga.h"
 
 void main() {

From c939c33b27ada55bf546641c76fe4fbd219c3c2b Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 21:20:04 +0200
Subject: [PATCH 2/8] Minor style change

---
 drivers/vga.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/vga.c b/drivers/vga.c
index c2e1dbe..5039b9c 100644
--- a/drivers/vga.c
+++ b/drivers/vga.c
@@ -38,7 +38,7 @@ void writechar(char c, unsigned int col, unsigned int row, int attribute_byte) {
 void clear_screen() {
 	for( int c = 0; c < MAX_COLS; c++ )
 		for( int r = 0; r < MAX_ROWS; r++ )
-			writechar(0x20, c, r, 0x0);
+			writechar(0x20, c, r, 0xf0);
 }
 
 void disable_vga_cursor() {

From 21d8767ec82cd5e0ae59b95c3c5080ccf6705c3c Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 21:20:17 +0200
Subject: [PATCH 3/8] Removed bloat

---
 kernel/kernel.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/kernel/kernel.c b/kernel/kernel.c
index 2620165..2d24fd9 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -1,5 +1,3 @@
-#define NULL ((void*)0x0)
-
 #include "../drivers/vga.h"
 
 void main() {

From 28aeaec3965ff05705a0aa459898244fab120912 Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 21:36:20 +0200
Subject: [PATCH 4/8] Cleanup

---
 drivers/vga.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/vga.c b/drivers/vga.c
index 5039b9c..150263a 100644
--- a/drivers/vga.c
+++ b/drivers/vga.c
@@ -1,9 +1,6 @@
 // VGA Graphics Library
 #include "../kernel/io.h"
 
-// VGA base address: 0xb8000
-// Charpos = 0xb8000 + 2(row*80 + col)
-
 // Memory
 #define VGA_ADDRESS 	(char*)0xb8000
 #define VGA_ADDRESS_MAX	(char*)0xb8fa0
@@ -11,7 +8,6 @@
 #define MAX_ROWS 25
 #define MAX_COLS 80
 
-// Global
 static unsigned int cursor_row = 0;
 static unsigned int cursor_col = 0;
 
@@ -32,6 +28,11 @@ void writechar(char c, unsigned int col, unsigned int row, int attribute_byte) {
 
 }
 
+void set_cursor_pos(unsigned int x, unsigned int y) {
+	cursor_col = x;
+	cursor_row = y;
+}
+
 /*
 	Graphics Functions
 */
@@ -50,11 +51,6 @@ void disable_vga_cursor() {
 /*
 	General Printing Functions
 */
-void set_cursor_pos(unsigned int x, unsigned int y) {
-	cursor_col = x;
-	cursor_row = y;
-}
-
 void print(char* str, int attribute_byte) {
 	for( char* c = str; *c != '\0'; c++ ) 
 		writechar(*c, (unsigned int)(c - str) + cursor_col, cursor_row, attribute_byte);

From dcb763a334a1650371a801394b9d7aa0af3a112e Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 21:39:27 +0200
Subject: [PATCH 5/8] Test code

---
 kernel/kernel.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/kernel.c b/kernel/kernel.c
index 2d24fd9..db63a5e 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -6,4 +6,8 @@ void main() {
 
 	set_cursor_pos(28, 2);
 	print("eOS Version 0.1 2021", 0xf0);
+
+	set_cursor_pos(0, 0);
+	for( int i = 0; i < 255; i++ )
+		println("X", i);
 }

From 4a56eb0156ff49738c991ffabe132dfb7985991a Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 21:53:06 +0200
Subject: [PATCH 6/8] Cleanup

---
 drivers/vga.c   | 6 +++---
 kernel/kernel.c | 2 ++
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/vga.c b/drivers/vga.c
index 150263a..8173d5a 100644
--- a/drivers/vga.c
+++ b/drivers/vga.c
@@ -28,9 +28,9 @@ void writechar(char c, unsigned int col, unsigned int row, int attribute_byte) {
 
 }
 
-void set_cursor_pos(unsigned int x, unsigned int y) {
-	cursor_col = x;
-	cursor_row = y;
+void set_cursor_pos(unsigned int col, unsigned int row) {
+	cursor_col = col;
+	cursor_row = row;
 }
 
 /*
diff --git a/kernel/kernel.c b/kernel/kernel.c
index db63a5e..290d9e5 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -7,7 +7,9 @@ void main() {
 	set_cursor_pos(28, 2);
 	print("eOS Version 0.1 2021", 0xf0);
 
+	/*
 	set_cursor_pos(0, 0);
 	for( int i = 0; i < 255; i++ )
 		println("X", i);
+	*/
 }

From f5771c0dc9823c5505a9032f4b26e92e8abb17ce Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 21:58:22 +0200
Subject: [PATCH 7/8] More cleanup

---
 drivers/vga.c | 25 ++++++++++++-------------
 drivers/vga.h |  3 +--
 2 files changed, 13 insertions(+), 15 deletions(-)

diff --git a/drivers/vga.c b/drivers/vga.c
index 8173d5a..e215b7f 100644
--- a/drivers/vga.c
+++ b/drivers/vga.c
@@ -1,4 +1,5 @@
 // VGA Graphics Library
+#include "vga.h"
 #include "../kernel/io.h"
 
 // Memory
@@ -11,10 +12,19 @@
 static unsigned int cursor_row = 0;
 static unsigned int cursor_col = 0;
 
+void vga_init() {
+	// Disable cursor
+	port_outb(0x0a, 0x3d4);
+	port_outb(0x20, 0x3d5);
+
+	// Clear screen
+	clear_screen();
+}
+
 /*
 	VGA & Memory Functions
 */
-char* get_vga_charpos_pointer(unsigned int col, unsigned int row) { 
+char* get_memory_charpos(unsigned int col, unsigned int row) { 
 	return (char*)(VGA_ADDRESS + 2*((row*80) + col)); 
 }
 
@@ -22,7 +32,7 @@ void writechar(char c, unsigned int col, unsigned int row, int attribute_byte) {
 	if( !attribute_byte ) 
 		attribute_byte = 0x0f;
 
-	char* mem = get_vga_charpos_pointer(col, row);
+	char* mem = get_memory_charpos(col, row);
 	*mem = c; 			// Write the character
 	*(mem+1) = attribute_byte;	// Write the attribute_byte
 
@@ -42,12 +52,6 @@ void clear_screen() {
 			writechar(0x20, c, r, 0xf0);
 }
 
-void disable_vga_cursor() {
-	port_outb(0x0a, 0x3d4);
-	port_outb(0x20, 0x3d5);
-}
-
-
 /*
 	General Printing Functions
 */
@@ -62,8 +66,3 @@ void println(char* str, int attribute_byte) {
 }
 
 
-// VGA Initialization Function
-void vga_init() {
-	disable_vga_cursor();
-	clear_screen();
-}
diff --git a/drivers/vga.h b/drivers/vga.h
index cf7a721..983fb09 100644
--- a/drivers/vga.h
+++ b/drivers/vga.h
@@ -1,7 +1,6 @@
-char* get_vga_charpos_pointer(unsigned int col, unsigned int row);
+char* get_memory_charpos(unsigned int col, unsigned int row);
 void writechar(char c, unsigned int col, unsigned int row, int colorcode);
 void clear_screen();
-void disable_vga_cursor();
 void set_cursor_pos();
 void print();
 void println();

From beb014a6b4a3f7ffa6c9211af450ae5f01d9faef Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Mon, 23 Aug 2021 22:00:19 +0200
Subject: [PATCH 8/8] Fixed minor bug

---
 drivers/vga.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/vga.c b/drivers/vga.c
index e215b7f..c53692b 100644
--- a/drivers/vga.c
+++ b/drivers/vga.c
@@ -14,8 +14,8 @@ static unsigned int cursor_col = 0;
 
 void vga_init() {
 	// Disable cursor
-	port_outb(0x0a, 0x3d4);
-	port_outb(0x20, 0x3d5);
+	port_outb(0x3d4, 0x0a);
+	port_outb(0x3d5, 0x20);
 
 	// Clear screen
 	clear_screen();
@@ -43,6 +43,7 @@ void set_cursor_pos(unsigned int col, unsigned int row) {
 	cursor_row = row;
 }
 
+
 /*
 	Graphics Functions
 */